This breather unit is a marked improvement over the customary dust caps or OEM breathers on equipment. When contaminated air enters the top of the breather, it passes through layered filter media, preventing solid particles from entering the breather and causing undue wear to your equipment surfaces. Filtered air passes through a bed of Power Breather silica gel, which removes harmful moisture from the air. The silica beads also work to attract moisture from inside the equipment reservoir during service or shut-down, keeping the equipment dry. For more click here.